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| Registros recuperados: 70 | |
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| Faria,Tiago C.; Guimarães,Karen L. A.; Rodrigues,Luís R. R.; Oliveira,Claudio; Lima,Flávio C.T.. |
| ABSTRACT A new species of Hyphessobrycon belonging to the Hyphessobrycon heterorhabdus species-group from the lower rio Tapajós, state of Pará, Brazil, is described. The new species is allocated into the Hyphessobrycon heterorhabdus species-group due to its color pattern, composed by an anteriorly well-defined, horizontally elongated humeral blotch that becomes diffuse and blurred posteriorly, where it overlaps with a conspicuous midlateral dark stripe that becomes blurred towards the caudal peduncle and the presence, in living specimens, of a tricolored longitudinal pattern composed by a dorsal red or reddish longitudinal stripe, a middle iridescent, golden or silvery longitudinal stripe, and a more ventrally-lying longitudinal dark pattern composed by... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biodiversity; Cryptic Species; DNA Barcoding; Rio Amazonas; Rio Tapajós.. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100207 |
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| Melo,Bruno F; Benine,Ricardo C; Mariguela,Tatiane C; Oliveira,Claudio. |
| A new species of Tetragonopterus is described from the rio Jari, a tributary to the left margin of rio Amazonas, at the border between Amapá and Pará States, northern Brazil. It is morphologically diagnosed from the other species of the genus (T. argenteus, T. chalceus, and T. rarus new combination) by the lozenge-shaped spot on the caudal peduncle vs. rounded to square spot on the other species. Partial sequences of the mitochondrial gene Cytochrome Oxidase C subunit I, from representatives of all valid species of Tetragonopterus, including this new species, were analyzed. The obtained results revealed a significant genetic distance between the new species and its congeners. A discussion on the new combination, Tetragonopterus rarus, is also provided. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: COI gene; Genetic distance; Mitochondrial DNA; Neotropical fish; Taxonomy. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000100002 |
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| Hilsdorf,Silva; Oliveira,Claudio; Lima,Flávio César Thadeo de; Matsumoto,Cristianne Kayoko. |
| The genus Brycon, the largest subunit of the Bryconinae, has 42 valid species distributed from southern Mexico to the La Plata River in Argentina. Henochilus is a monotypic genus, comprising a single species (H. wheatlandii) found in the upper Rio Doce basin. In the present study, partial sequences of the mitochondrial gene 16S were obtained for fifteen species of Brycon and for Henochilus wheatlandii. The results showed that the genus Brycon is paraphyletic, since Henochilus is the sister-group of B. ferox and B. insignis. The most basal species analyzed were the trans-Andean species B. henni, B. petrosus, and B. chagrensis. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phylogeny; Molecular systematics; Mitochondrial DNA; Fish evolution; Systematic. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200034 |
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| Porto-Foresti,Fábio; Oliveira,Claudio; Tabata,Yara A.; Rigolino,Marcos G.; Foresti,Fausto. |
| In salmonid species, nucleolar organizing regions (NORs) have frequently been found on a single chromosome pair. However, some other, smaller yet active NORs have also been described. In the present study, NORs were found to be located in different positions on the chromosomes of 12 rainbow trout samples (11 cultivated and one naturalized stocks). Three phenotypes were found: 1) NORs located on two submetacentric chromosomes, in a subterminal position on the short arm (AA); 2) NORs located on two submetacentric chromosomes, in a subterminal position on the long arm (BB); and 3) NORs located on two submetacentric chromosomes, one in a subterminal position on the short arm, and the other in a subterminal position on the long arm (AB). Phenotype AA was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: NOR polymorphism; Fish cytogenetics; Rainbow trout. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572002000400009 |
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| Nirchio,Mauro; Masache,Maria Cecilia; Paim,Fabilene Gomes; Cioffi,Marcelo de Bello; Moreira Filho,Orlando; Barriga,Ramiro; Oliveira,Claudio; Rossi,Anna Rita. |
| ABSTRACT Parodontidae is a relatively small group of Neotropical characiform fishes consisting of three genera (Apareiodon, Parodon, and Saccodon) with 32 valid species. A vast cytogenetic literature is available on Apareiodon and Parodon, but to date, there is no cytogenetic data about Saccodon, a genus that contains only three species with a trans-Andean distribution. In the present study the karyotype of S. wagneri was described, based on both conventional (Giemsa staining, Ag-NOR, C-bands) and molecular (repetitive DNA mapping by fluorescent in situ hybridization) methods. A diploid chromosome number of 2n = 54 was observed in both sexes, and the presence of heteromorphic sex chromosomes of the ZZ/ZW type was detected. The W chromosome has a terminal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ag-NOR; Cytogenetics; FISH; Heterochromatin; ZW sex chromosomes. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100203 |
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| Spadella,Maria A.; Oliveira,Claudio; Quagio-Grassiotto,Irani. |
| In Corydoradinae, the presence of spermatids in the lumen of the testicular tubules together with spermatozoa suggests that spermatogenesis is of the semicystic type, whereas in Callichthyinae, sperm production occurs entirely within spermatocysts in the germinal epithelium, characterizing cystic spermatogenesis. Spermiogenesis in Callichthyinae is characterized by an initial lateral development of the flagellum, the presence of nuclear rotation to different degrees, an eccentric or medial formation of a nuclear fossa, formation of a cytoplasmic channel, and presence of centriolar migration, being more similar to type I spermiogenesis. In Corydoradinae, spermiogenesis is characterized by eccentric development of the flagellum, the absence of nuclear... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Catfish; Spermatid; Spermatozoa; Phylogeny; Morphology. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300014 |
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| Maistro,Edson Luis; Oliveira,Claudio; Foresti,Fausto. |
| Cytogenetic and morphological studies were carried out on nine local populations of Astyanax scabripinnis paranae. All populations exhibited 2n = 50 chromosomes as well as conspicuous differences involving karyotype morphology, number and position of nucleolar organizer regions (NORs) and amount and/or locations of constitutive heterochromatin blocks. A quantitative study of the cytogenetic data showed that eight populations possessed different karyotypes. Morphological analyses based on nine measurements and two meristic parameters were effective in establishing clear identification of five populations. Comparative analysis of cytogenetic and morphological traits suggests that chromosomal changes have occurred at a more rapid rate than morphological... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200005 |
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| Tenório,Renata Cristina Claudino de Oliveira; Vitorino,Carla de Andrade; Souza,Issakar Lima; Oliveira,Claudio; Venere,Paulo Cesar. |
| Astyanax is a diverse group of Neotropical fishes, whose different forms occupy different environments. This great diversity is also reflected on cytogenetic aspects and molecular markers, which have repeatedly been demonstrated by cytogenetic studies. In order to characterize the karyotype of species of this genus, six species were studied: Astyanax altiparanae, A.argyrimarginatus, A. elachylepis, A. xavante, and two new species provisionally called Astyanax sp. and A. aff. bimaculatus. A detailed cytogenetic study based on conventional staining with Giemsa, AgNORs, C-banding, base-specific fluorochromes, and FISH using ribosomal genes 18S and 5S was conducted, aiming to understand some of the chromosomal mechanisms associated with the high... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: C-banding; CMA3 and DAPI fluorochromes; Fish chromosome; RDNA genes; NORs. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000300553 |
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| Quagio-Grassiotto,Irani; Spadella,Maria Angélica; Carvalho,Márcio de; Oliveira,Claudio. |
| The data obtained in the present study on spermiogenesis and spermatozoal ultrastructure of Pseudopimelodidae and Heptapteridae show that they share some characteristics, but greatly differ from each other. The main differences are the occurrence of type I spermiogenesis in Pseudopimelodidae and type III in Heptapteridae, the presence of nuclear fossa in Pseudopimelodidae and its absence in Heptapteridae, the presence of long midpiece in Pseudopimelodidae and short midpiece in Heptapteridae, the presence of cytoplasmic canal in Pseudopimelodidae and its absence in Heptapteridae, the presence of many large vesicles in the midpiece of Pseudopimelodidae and the presence of very long vesicles placed in the peripheral distal region in Heptapteridae, and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Catfish; Spermatid; Sperm; Structure; Phylogeny. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252005000300008 |
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| Martinez,Emanuel Ricardo Monteiro; Zawadzki,Claudio Henrique; Foresti,Fausto; Oliveira,Claudio. |
| In this work, we analyzed the karyotypes of five species. Hypostomus cf. heraldoi, from the Mogi-Guaçu River, had 2n = 72 chromosomes, with a nucleolar organizer region (NOR) in one chromosomal pair. Hypostomus regani, from the Mogi-Guaçu River had 2n = 72 chromosomes with NORs in two chromosomal pairs. Hypostomus sp., from the Mogi-Guaçu River basin, had 2n = 68 chromosomes, with NORs in two chromosomal pairs. Hypostomus aff. agna, from Cavalo Stream, had 2n = 74 chromosomes with NORs in two chromosomal pairs. Hypostomus cf. topavae, from Carrapato Stream, had 2n = 80 chromosomes, with NORs in two chromosomal pairs. Hypostomus species showed marked diversity in the karyotypic formula, which suggested the occurrence of several Robertsonian rearrangements... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomes; Evolution; Hypostominae; Neotropical fish; NOR. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000400006 |
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| Martinez,Emanuel Ricardo Monteiro; Nirchio,Mauro; Granado,Angel; Foresti,Fausto; Oliveira,Claudio. |
| Cytogenetic analyses performed in Cephalosilurus apurensis, Microglanis aff. cottoides and Pseudopimelodus bufonius revealed that the three species have 2n = 54 chromosomes: C. apurensis presented six metacentric (M), 28 submetacentric (SM), 14 subtelolocentric (ST), and six acrocentric (A) chromosomes, while M. aff. cottoides showed 10M, 32SM, 10ST and 2A, and P. bufonius had 12M, 30SM and 12ST. The nucleolus organizer regions (NORs) were present on the short arm of a middle-sized ST pair, identified as pair 19, in C. apurensis NORs were found on the short arm of a middle-sized ST (pair 23) and on the long arm of a middle-sized ST (pair 22) in M. aff. cotttoides and on the short arm of three middle-sized ST pairs, identified as pairs 9, 10 and 11, in P.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Chromosomes; C-banding; Ag-NOR; Fish. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000400015 |
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| Nirchio,Mauro; Martinez,Emanuel Ricardo Monteiro; Foresti,Fausto; Oliveira,Claudio. |
| Despite their ecological and economical importance, fishes of the family Ariidae are still genetically and cytogenetically poorly studied. Among the 133 known species of ariids, only eight have been karyotyped. Cytogenetic analyses performed on Genidens barbus and Sciades herzbergii revealed that both species have 2n = 56 chromosomes and Cathorops aff. mapale has 2n = 52 chromosomes: Genidens barbus has 10 Metacentrics (M), 14 Submetacentrics (SM), 26 Subtelocentrics (ST), and 6 Acrocentrics (A), Sciades herzbergii has 14M, 20SM, 18ST and 4A, whereas Cathorops aff. mapale has 14M, 20SM, and 18ST. The nucleolus organizer regions (NORs) were found in a single chromosome pair on the short arm of a large-sized ST pair in Genidens barbus and on the short arm of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; Ag-NORs; Chromosome evolution; Chromosome rearrangements; Fish. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200011 |
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| Nirchio,Mauro; Oliveira,Claudio; Ferreira,Daniela C.; Rondón,Rodolfo; Pérez,Julio E.; Hett,Anne Kathrin; Rossi,Anna Rita; Sola,Luciana. |
| Lutjanidae, commonly known as snappers, includes 105 species, grouped in four subfamilies. In spite of the high number of species and of its worldwide distribution, the family has been little investigated and the phylogenetic relationships among some of its genera and species are still cause for debate. Only a small number of the species has been cytogenetically analysed. This study reports the first description of the karyotype of Rhomboplites aurorubens as well as data concerning the distribution of the constitutive heterochromatin and the location of the 18S rRNA and the 5S rRNA genes. Specimens of Ocyurus chrysurus from Venezuela were also investigated for the same cytogenetic features. Both species have a 48 uniarmed karyotype, but R. aurorubens has a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: C-banding FISH; Karyotype NORs Ribosomal genes. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000400005 |
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| Nirchio,Mauro; Rondón,Rodolfo; Oliveira,Claudio; Ferreira,Irani A.; Martins,Cesar; Pérez,Julio; Sola,Luciana; Rossi,Anna Rita. |
| In the present study, three species of Lutjaninae, Lutjanus analis, L. griseus and L. synagris, were analyzed by conventional Giemsa staining, C-banding and silver staining, to reveal active Nucleolus Organizer Regions (NORs). Fluorescent in situ hybridization (FISH) was also applied to establish the number and location of the ribosomal gene clusters (18S and 5S rRNA genes). Counts of diploid metaphasic cells revealed a diploid modal chromosome complement composed of 48 acrocentric chromosomes in both L. analis and L. griseus. Two cytotypes were observed in L. synagris: cytotype I, with 2n=48 acrocentric chromosomes, found in 19 specimens, and cytotype II, with 46 acrocentric chromosomes and one large metacentric, found in two specimens. The large... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Ribosomal genes; NOR polymorphism; C-banding; Robertsonian rearrangement. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100012 |
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| Registros recuperados: 70 | |
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